Aluminum alloy.



WILLIAM A. MQADAMS, or aYsnonn, new YORK.

ALUMINUM ALLOY.

No Drawing.

Specification of Letters Patent. Application filed August 15, 1913. Serial No. 784,918.

Patented Apr. 71,1914.

To all whom it may concern Be it. known that I, WILLIAM A. Mo

AoAMs, a citizen ofthe United States, and resident of Bay Shore, in the county of Suffolk and State of New York, have invented a new and useful Aluminum Alloy, of which the following is a specification.

My invention relates to an aluminum alloy, with the object in view of providing an inexpensive allo suitable for casting purposes, which will not tarnish and which will possess the qualities of great fluidity and stren th.

l/Vith t eseends in view, m invention consists in an alloy composed 0 aluminum, 'zinc, copper and silver in which the amount of zinc exceeds the amount. of'copper and the amount of aluminum exceeds the amount of zinc.

The aforesaid elements are preferably combined in the proportion of 70 parts by weight of aluminum; 26 parts by weight of zinc; 3 parts by weight of copper and 1 part by weight of silver.

In making the alloy, about one-third of the aluminum is preferably first melted and the copper and silver introduced into the molten aluminum, and the mass raised to such a degree as to alloy and melt the copper and silver intothe melted aluminum; then the cold balance of the aluminum is added and when melted the whole is well agitated or stirred so as to bring the molecules of the different elements into'intimate contact by a method of alloying wherein two-thirds of the aluminum'is not heated to such a high heat as the first third was. Now the mass is cooled so as to show but a light redness and the zinc is introduced and the mass stirred so as to mix and alloy it well together. The mass may then be poured into molds for making the desired castings or it may be cooled into ingots and then subsequently reheated to a fluid state for casting purposes. I I

It will be found in practice that the alloy composed as above will have such a degree of fluidity that it will take the smallest indentations of the mold with great accuracy and the casting will have the ver desirable features of being light, non-tarnishable, with a silver-like surface and will be sufficiently strong to be utilized in a great majority of places Where brass is now used. The cast mgs will also be found capable of resisting aclds and alkalis to an extent which will render them exceedingly desirable for general use. The introduction of silver in such a small proportion adds little to the expense of the casting and at the same time serves an important part in enabling the casting to resist alkalis and also in giving the casting a permanent silver-like color. 1

What I claim is:

1. An aluminum alloy composed of aluminum, zinc, copper and silver in which the amount of copper is greater than the amount of silver, the amount of zinc is greater than the amount of copper and the amount of aluminum is greater than the amount of zinc.

2. An aluminum alloy composed of aluminum, zinc, copper and silver combined substantially in the proportions by weight of 70 parts. of aluminum, 26 parts of zinc, 3

parts of copper and 1 part of silver.

In testimony, that I claim the foregoing as my invention, I have signed m name in presenceof. two witnesses, this ourteenth day of i ugust, 1913. 4

' WILLIAM A. McADAMS.

Witnesses: v

F. GEORGE BARRY, LIDA' M. EGBERT. 

